THURSDAY, Jan. 14, 2016 (HealthDay News) -- Seniors who are healthy but have low blood levels of bicarbonate are at higher risk for premature death, a new study contends.

Bicarbonate plays an important role in maintaining the body's pH balance. Fruits and vegetables are a source of bicarbonate.

Researchers looked at nearly 2,300 Americans, ages 70 to 97, who were followed for an average of just over 10 years. During that time, those who were healthy and had normal or high bicarbonate levels had a similar risk of dying, but those with low bicarbonate levels had a 24 percent increased risk of death.

The study was published online Jan. 14 in the Clinical Journal of the American Society of Nephrology.

"What we found was that generally healthy older people with low levels of bicarbonate had a higher risk of death," study author Dr. Kalani Raphael, from the University of Utah, said in a journal news release. "Adding the pH measurement into the equation didn't change the results, which is important because pH is not routinely measured.

The findings suggest that bicarbonate levels in the blood are an important health indicator and that future studies should look at whether increasing bicarbonate levels could extend life.

While the study found a link between bicarbonate levels and risk of death, it didn't prove cause-and-effect.